Legal psychology refers to psychological theory, research, and practice directly pertinent to the law and legal issues. It focuses on psycholegal research and contacts with judges, lawyers, and other law-related professionals in a wide range of contexts. The origins of legal psychology can be traced to the work of experimental psychologists in Europe in the 19th century, particularly in relation to the psychology of testimony (Mulberger, 2009; Sporer, 1982, 2008) and most particularly to the testimony of children, whose memory of events was considered unreliable (Lipmann, 1911). We discuss this work shortly.
U.S. Origins of Legal Psychology
Do chestnut or oak trees lose their leaves earlier in autumn? Do horses in the field stand with head or tail to the wind? In which direction do the seeds of an apple point? What was the weather one week ago today?
When J. McKeen Cattell posed these questions to 56 college students at Columbia University in March 1893, he was probably conducting one of the first American studies, albeit an informal one, on the psychology of testimony. The questions he asked his students were similar to those that “might naturally be asked in a court of justice” (Cattell, 1895, p. 761). His subjects were allowed 30 seconds to consider their answers, then told to write their responses and indicate their degree of confidence in each answer.
When Cattell conducted his informal and preliminary study, it was reasonably well established that eyewitness accounts of events were unreliable and incomplete. As we will see shortly, both French and German psychologists were familiar with the powerful influence of suggestion over sensation and perception, having conducted substantial research in these areas. The specific conditions under which testimony was inaccurate were not known, however. Cattell (1895) noted: “An unscrupulous attorney can discredit the statements of a truthful witness by cunningly selected questions. The jury, or at least the judge, should know how far errors in recollection are normal and how they vary under different conditions” (p. 761). But Cattell himself was surprised at both the degree of inaccuracy he uncovered and the wide range of individual differences in the levels of confidence expressed by the students. Answers to the weather question, for example, were “equally distributed over all kinds of weather which are possible at the beginning of March” (p. 761). Some students were nearly always sure they were correct, even when they were not, while others were consistently uncertain and hesitant in their answers, even when they were correct.
Cattell’s study probably was the genesis of modern forensic psychology in the United States, because it sparked the interest of other researchers in the psychology of testimony, which remains to this day a dominant research interest among legal psychologists. Joseph Jastrow immediately replicated Cattell’s “experiment” at the University of Wisconsin and obtained similar results (Bolton, 1896). Aside from this brief flirtation, however, American psychologists did not immediately embrace the study of legal issues. Psychologists in Europe seemed more intrigued—they had long been interested in the psychological concepts involved. First, Alfred Binet (1900) replicated Cattell’s project in France. In addition, he summarized relevant experiments on the psychology of testimony that were being conducted in Europe, and he eventually called for a “science psycho-judiciaire” (Binet, 1905; Binet & Clarparede, 1906).
European Origins of Legal Psychology
Most significant for the historical development of forensic psychology was the apparent fascination Cattell’s experiment and Binet’s work held for (Louis) William Stern (1902, 1910, 1939), who had received his doctorate in psychology at the University of Berlin under the tutelage of Hermann Ebbinghaus. In 1901, Stern collaborated with the criminologist F. v. Liszt in an attempt to lend realism to the Cattell design. Stern and Liszt conducted a “reality experiment” in a law class, staging a bogus quarrel between two students over a scientific controversy.
As Stern later recounted it, the argument accelerated until one student drew a revolver (Stern, 1939). At this point, the professor intervened and asked for written and oral reports from the class about aspects of the dispute. Although the witnesses were law students who, Stern asserted, should have known the pitfalls of testifying, none could give a faultless report. The number of errors per individual ranged from 4 to 12. Moreover, the researchers found that inaccuracies increased with respect to the second half of the scenario, when excitement and tension were at their peak. They concluded—tentatively—that “affective reactions inhibit exact observation and reliable remembrance” (Stern, 1939, p. 11).
By his own account, Stern (1939) was more interested in basic research than its application. “Indeed, when I began in 1901 to examine the correctness of recollection among my students, I was determined by theoretical interests in the realm of memory rather than by any practical considerations. Yet once confronted with the results, I realized the importance of this research beyond the borders of mere academic psychology” (p. 4).
Throughout that first decade of the 20th century, Stern was an active researcher in the psychology of testimony. He also helped establish and edited the first journal on the psychology of testimony, Betrage zur Psychologie der Aussage (Contributions to the Psychology of Testimony), which was published in Leipzig. The journal was superseded in 1907 by the much broader Zeitschrift fur Angewande Psychologie (Journal of Applied Psychology), edited by Stern and his colleague Otto Lipmann. In a cautionary note about his research, Stern stressed that most witnesses did not intentionally falsify their reports. Rather, the subtle and common problem created was one of unintentional falsification: “Subjective sincerity does not guarantee objective truthfulness,” he wrote (1939, p. 13). In his research, Stern concluded among other things that: (1) leading and suggestive questions contaminate the accuracy of eyewitness accounts of critical events; (2) there are important differences between adult and child witnesses; (3) lineups are of limited value when the members are not matched for age and physical appearance; and (4) interceding events between an initial event and its recall can have drastic effects on memory. Therefore, modern forensic psychology began as legal psychology with empirical research on the psychology of testimony.
During these early years, European psychologists interacted much more regularly with the law than their American counterparts did. Despite the fact that Stern and Binet, for example, did not initially intend that their research on suggestibility and reliability of observation be applied to the law, they eventually did recommend such an application. Thus European, particularly German, psychologists conducted experimental research, lectured, and consulted with jurists, particularly in the latter half of the 19th century and into the 20th (Mulberger, 2009; Sporer, 1982).
Return to overview of the History of Forensic Psychology.